Microstructure of In/sub x/Ga/sub 1-x/N thick epitaxial layers

Abstract

0.1/spl mu/m thick In/sub x/Ga/sub 1-x/N epitaxial layers were grown by metal organic chemical vapor deposition on undoped GaN. GaN layers were /spl sim/2.7/spl mu/m thick and were grown on c-plane sapphire using low-temperature GaN buffer layers. Convergent-beam electron diffraction (CBED) was used to observe the local strain and dislocation density. The indium concentration of the In/sub x/Ga/sub 1-x/N was measured by Rutherford backscattering spectrometry (RBS). Using scanning electron microscopy and transmission electron microscopy In/sub x/Ga/sub 1-x/N layers cathodoluminescence spectra were studied.